| (19) |
 |
|
(11) |
EP 0 209 641 A3 |
| (12) |
EUROPEAN PATENT APPLICATION |
| (88) |
Date of publication A3: |
|
20.04.1988 Bulletin 1988/16 |
| (43) |
Date of publication A2: |
|
28.01.1987 Bulletin 1987/05 |
| (22) |
Date of filing: 14.04.1986 |
|
|
| (84) |
Designated Contracting States: |
|
BE DE FR GB IT NL |
| (30) |
Priority: |
22.07.1985 US 757249
|
| (71) |
Applicant: DeSOTO, INC. |
|
() |
|
| (72) |
Inventors: |
|
- Krajewski, John J.
()
- Bishop, Timothy E.
()
- Coady, Clive J.
()
- Zimmerman, John M.
()
- Noren, Gerry K.
()
- Fisher, Christopher E.
()
|
|
| |
|
| (54) |
Ultraviolet curable coatings for optical glass fiber base on a polyfunctional core |
(57) An ultraviolet curing liquid coating composition which, when cured with ultraviolet
light in the presence of an appropriate photoinitiator, provides a coating adapted
for the coating of optical glass fiber. This coating composition comprises as the
essential component, an acrylate-terminated polyurethane oligomer based on a polyfunctional
core which is at least trifunctional and which supports one branch for each functionality
in the core. Each of the branches leads to an acrylate-functional terminal group,
with there being from about 150 to about 2500 units of molecular weight in each branch
between the trifunctional core and the acrylate-functional terminal group. Depending
primarily upon the molecular weight of the branches, one can provide coating compositions
for buffer coat, single coat or topcoat use.